In setting aside a 2009 judgment by the Delhi High Court that decriminalised homosexual sex, the Supreme Court of India on Wednesday ruled that Section 377 of the Indian Penal Code was constitutionally valid.

Section 377 - ‘‘Unnatural offences’’ - states that ‘‘carnal intercourse against the order of nature with any man, woman, or animal’’ shall be punishable by life imprisonment.

Framed by the British in 1860, Section 377 does not specifically define ‘unnatural offences’, but it is has historically been interpreted as an anti-sodomy law. Petitions brought before the Supreme Court appealing the lower court’s ruling, argued that gay and lesbian sex are against the order of nature.

The law now more than 150 years old, also equates homosexual relationships with bestiality.

The court said on Wednesday that parliament had the power to remove Section 377 from the law of the land, but that the court could not legalise homosexual relationships.

‘‘It is for the legislature to look into the desirability of deleting Section 377 of the IPC,’’ the court said.

No-one in India has ever been convicted under the law, but campaigners argue its presence on the statute books contributes to the oppression of homosexuals, who live largely closeted in India, and stifles HIV prevention efforts.

The decision was condemned by human right groups. Lesbian, Gay, Bisexual and Transgender activists inside the courtroom broke down in tears at the verdict.

‘‘This decision is a body blow to people’s rights to equality, privacy and dignity,’’ G Ananthapadmanabhan, chief executive of Amnesty International India, said.

‘‘It is hard not to fell let down by this judgment, which has taken India back several years in its commitment to protect basic rights.’’

Voices Against 377, a sexual rights activist group, said the decision was ‘‘a bump in the road’’ in the struggle for equality.

‘‘We are very sad. People of this country are progressive, we have tons of support.

‘‘India as a country is moving forward. We have lots of support from parents, [but] this is a setback.’’

The order was ‘‘a step backwards towards barbarism and medievalism’’, tweeted historian Ramachandra Guha.

The Naz Foundation, which works to promote sexual health in India, brought a petition before the Delhi Supreme Court in 2009, arguing the laws that criminalised homosexuality were an infringement of people’s human rights.

But the Supreme Court reviewed the Delhi High Court decision after a slew of petitions protesting the decriminalisation of homosexuality.

The All India Muslim Personal Law Board, the Utkal Christian Council, and the Apostolic Churches Alliance argued homosexuality should be outlawed.

B.P. Singhal, a leader of the Bharatiya Janata Party, the party looking increasingly likely to win power in next year’s national elections, was also a petitioner arguing against gay rights.

Law Minister Kapil Sibal said the government would respect the court’s judgment.

‘‘The Supreme Court is the final arbiter, it has to be respected by the government.

‘‘We [parliament] have the prerogative to make laws. Let us exercise that prerogative,’’ he said but would not comment further.